This invention relates to an olefin polymer composed of the reaction product of a functionalized polypropylene and a amidoamine. This invention also relates to thermoplastic resin blends containing the olefin polymer and polypropylene.
The in situ formation of compatibilizers for polyblends is rapidly gaining popularity. In the last few years, more and more cases have been reported where advantage is taken of the presence of reactive groups to form a graft or a block or a random copolymer, which could act as a compatibilizer for a mixture of two or more polymers. For example, Process Requirements of the Reactive Compatibilization of Nylon 6/Polypropylene Blends by S. S. Dagli, M. Xanthos and J. A. Biensenberger: Polymer Processing Institute at Stevens Institute of Technology, Hoboken, N.J. 07030 reveals an acrylic acid grafted modified polypropylene used with a blend of nylon-6 and polypropylene.
Thermoplastic resin compositions containing polypropylene are well known in the art (e.g. U.S. Pat. No. 5,208,081). U.S. Pat. No. 5,179,164 describes a polypropylene/polyamide composition suitable for producing moldings. The patent describes an ethylene copolymer useful as an adhesion promoter. Moreover, the patent indicates that maleic acid is a suitable monomer for preparing the ethylene copolymer.
European patent application 0 367 832 discloses a resin composition containing an olefinic polymer having acid anhydride groups. As in U.S. Pat. No. 5,179,164, the novel compound is blended with a polyamide.
Although the compositions of the above-mentioned patents take advantage of copolymers to alter some properties of thermoplastic resin compositions, they do not succeed in significantly improving the resilience of the resin to meet requirements for high impact applications. Hence, it would be desirable to develop a copolymer blend that would significantly improve the impact resistance and modify the water absorbance and melt rheology of the resin compositions.